<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">

	<title>ASLayoutSpec(Subclassing) Category Reference</title>

	<link rel="stylesheet" href="../css/style.css">
	<meta name="viewport" content="initial-scale=1, maximum-scale=1.4">
	<meta name="generator" content="appledoc 2.2.1 (build 1334)">
</head>
<body class="appledoc">
	<header>
		<div class="container" class="hide-in-xcode">
			
			<h1 id="library-title">
				<a href="../index.html">  </a>
			</h1>

			<p id="developer-home">
				<a href="../index.html">AsyncDisplayKit</a>
			</p>
			
		</div>
	</header>

	<aside>
		<div class="container">
			<nav>
				<ul id="header-buttons" role="toolbar">
					<li><a href="../index.html">Index</a></li>
<li><a href="../hierarchy.html">Hierarchy</a></li>

					<li id="on-this-page" role="navigation">
						<label>
							On This Page

							<div class="chevron">
								<div class="chevy chevron-left"></div>
								<div class="chevy chevron-right"></div>
							</div>

							<select id="jump-to">
	<option value="top">Jump To&#133;</option>
	

	
	
	<option value="tasks">Tasks</option>
	
	

	
	

	

	
	<optgroup label="Instance Methods">
		
		<option value="//api/name/childAtIndex:">- childAtIndex:</option>
		
		<option value="//api/name/layoutElementToAddFromLayoutElement:">- layoutElementToAddFromLayoutElement:</option>
		
		<option value="//api/name/setChild:atIndex:">- setChild:atIndex:</option>
		
	</optgroup>
	
	
</select>
						</label>
					</li>
				</ul>
			</nav>
		</div>
	</aside>

	<article>
		<div id="overview_contents" class="container">
			<div id="content">
				<main role="main">
					<h1 class="title">ASLayoutSpec(Subclassing) Category Reference</h1>

					
					<div class="section section-specification"><table cellspacing="0"><tbody>
						<tr>
	<th>Declared in</th>
	<td>ASLayoutSpec+Subclasses.h</td>
</tr>
						</tbody></table></div>
					

                    

					
					
					<div class="section section-tasks">
						<a title="Tasks" name="tasks"></a>
						

						
						

						<div class="task-list">
							<div class="section-method">
	<a name="//api/name/layoutElementToAddFromLayoutElement:" title="layoutElementToAddFromLayoutElement:"></a>
	<h3 class="method-title"><code><a href="#//api/name/layoutElementToAddFromLayoutElement:">&ndash;&nbsp;layoutElementToAddFromLayoutElement:</a></code>
</h3>

	<div class="method-info">
		<div class="pointy-thing"></div>

		<div class="method-info-container">
			
			
			<div class="method-subsection brief-description">
				<p>Helper method for finalLayoutElement support</p>
			</div>
			
		    

			<div class="method-subsection method-declaration"><code>- (id&lt;ASLayoutElement&gt;)layoutElementToAddFromLayoutElement:(id&lt;ASLayoutElement&gt;)<em>child</em></code></div>

		    
			

			

			

			
			<div class="method-subsection discussion-section">
				<h4 class="method-subtitle">Discussion</h4>
				<div class="warning"><p><strong>Warning:</strong> If you are getting recursion crashes here after implementing finalLayoutElement, make sure
that you are setting isFinalLayoutElement flag to YES. This must be one BEFORE adding a child
to the new ASLayoutElement.</p>

<p>For example:
- (id<a href="../Protocols/ASLayoutElement.html">ASLayoutElement</a>)finalLayoutElement
{
ASInsetLayoutSpec *insetSpec = [[ASInsetLayoutSpec alloc] init];
insetSpec.insets = UIEdgeInsetsMake(10,10,10,10);
insetSpec.isFinalLayoutElement = YES;
[insetSpec setChild:self];
return insetSpec;
}</p></div>
			</div>
			

			

			

			
			<div class="method-subsection declared-in-section">
				<h4 class="method-subtitle">Declared In</h4>
				<p><code class="declared-in-ref">ASLayoutSpec+Subclasses.h</code></p>
			</div>
			
			
		</div>
	</div>
</div><div class="section-method">
	<a name="//api/name/setChild:atIndex:" title="setChild:atIndex:"></a>
	<h3 class="method-title"><code><a href="#//api/name/setChild:atIndex:">&ndash;&nbsp;setChild:atIndex:</a></code>
</h3>

	<div class="method-info">
		<div class="pointy-thing"></div>

		<div class="method-info-container">
			
			
			<div class="method-subsection brief-description">
				<p>Adds a child with the given identifier to this layout spec.</p>
			</div>
			
		    

			<div class="method-subsection method-declaration"><code>- (void)setChild:(id&lt;ASLayoutElement&gt;)<em>child</em> atIndex:(NSUInteger)<em>index</em></code></div>

		    
			
			<div class="method-subsection arguments-section parameters">
				<h4 class="method-subtitle parameter-title">Parameters</h4>
				<table class="argument-def parameter-def">
				
					<tr>
						<th scope="row" class="argument-name"><code>child</code></th>
						<td><p>A child to be added.</p></td>
					</tr>
				
					<tr>
						<th scope="row" class="argument-name"><code>index</code></th>
						<td><p>An index associated with the child.</p></td>
					</tr>
				
				</table>
			</div>
			

			

			

			
			<div class="method-subsection discussion-section">
				<h4 class="method-subtitle">Discussion</h4>
				<p>Every ASLayoutSpec must act on at least one child. The ASLayoutSpec base class takes the
responsibility of holding on to the spec children. Some layout specs, like ASInsetLayoutSpec,
only require a single child.</p>

<p>For layout specs that require a known number of children (ASBackgroundLayoutSpec, for example)
a subclass can use the setChild method to set the &ldquo;primary&rdquo; child. It should then use this method
to set any other required children. Ideally a subclass would hide this from the user, and use the
setChild:forIndex: internally. For example, ASBackgroundLayoutSpec exposes a backgroundChild
property that behind the scenes is calling setChild:forIndex:.</p>
			</div>
			

			

			

			
			<div class="method-subsection declared-in-section">
				<h4 class="method-subtitle">Declared In</h4>
				<p><code class="declared-in-ref">ASLayoutSpec+Subclasses.h</code></p>
			</div>
			
			
		</div>
	</div>
</div><div class="section-method">
	<a name="//api/name/childAtIndex:" title="childAtIndex:"></a>
	<h3 class="method-title"><code><a href="#//api/name/childAtIndex:">&ndash;&nbsp;childAtIndex:</a></code>
</h3>

	<div class="method-info">
		<div class="pointy-thing"></div>

		<div class="method-info-container">
			
			
			<div class="method-subsection brief-description">
				<p>Returns the child added to this layout spec using the given index.</p>
			</div>
			
		    

			<div class="method-subsection method-declaration"><code>- (nullable id&lt;ASLayoutElement&gt;)childAtIndex:(NSUInteger)<em>index</em></code></div>

		    
			
			<div class="method-subsection arguments-section parameters">
				<h4 class="method-subtitle parameter-title">Parameters</h4>
				<table class="argument-def parameter-def">
				
					<tr>
						<th scope="row" class="argument-name"><code>index</code></th>
						<td><p>An identifier associated with the the child.</p></td>
					</tr>
				
				</table>
			</div>
			

			

			

			

			

			

			
			<div class="method-subsection declared-in-section">
				<h4 class="method-subtitle">Declared In</h4>
				<p><code class="declared-in-ref">ASLayoutSpec+Subclasses.h</code></p>
			</div>
			
			
		</div>
	</div>
</div>
						</div>
						
					</div>
					
					

                    
                    
          
				</main>

				<footer>
					<div class="footer-copyright">
						
						<p class="copyright">Copyright &copy; 2016 AsyncDisplayKit. All rights reserved. Updated: 2016-11-05</p>
						
						
						<p class="generator">Generated by <a href="http://appledoc.gentlebytes.com">appledoc 2.2.1 (build 1334)</a>.</p>
						
					</div>
				</footer>
			</div>
		</div>
	</article>

	<script src="../js/script.js"></script>
</body>
</html>